The Patriots have been the cream of the crop in the NFL ever since Bill Belichick took over as head coach in 2000. But the three-time Super Bowl champions have been embroiled in some off-the-field scandals over the years. The latest is accusations the Patriots deflated footballs in their AFC Championship win last week.

Here's a look at some of the most memorable controversies over the last two decades under Belichick.

BELICHICK'S MESSY ARRIVAL IN NEW ENGLAND

Long before Belichick and Tom Brady were winning Super Bowls in New England, Belichick was a coach with the New York Jets. When Jets' head coach Bill Parcells stepped down in 1999, it was already decided that Belichick would succeed him in New York.

The news conference to introduce Belichick as the new head coach turned out to be quite the opposite. Belichick scribbled his resignation on a piece of paper: "I resign as HC of the NYJ." Belichick then delivered a resignation announcement.

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Head coach Bill Belichick of the New York Jets resigns from the job at a press conference just one day after accepting the position at Hempstead, New York on Jan. 4, 2000.

The Jets demanded compensation from the Patriots because Belichick was still under contract with the team. The NFL stepped in and the Jets were awarded the Patriots' first-round draft pick in 2000. This was also the opening salvo in a heated Jets-Patriots rivalry that continues to this day.

SPY-GATE

Perhaps the most publicized scandal involving the Patriots took place on Sept. 9, 2007 when the team was caught illegally videotaping Jets' coaches' defensive signals. And thus the term "spy-gate" was introduced to the sports world.

Belichick later acknowledged that he violated NFL rules prohibiting filming opponents' signals but insisted there was no intent to hide what he was doing.

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Head coach Bill Belichick of the New England Patriots during the 2015 AFC Championship Game against the Indianapolis Colts, Jan. 18, 2015 in Foxboro, Mass.

"I made a mistake," Belichick said in a televised interview. "I was wrong. I was wrong."

Even 13 years after the infamous "tuck rule" game, critics still believe it's a game the Patriots should have never won.

Let's set the scene: It was Jan. 19, 2002 and the Patriots were facing the Oakland Raiders in a divisional playoff game in the snow at Foxboro Stadium, the former home of the Pats. The Raiders were leading the Patriots in the fourth quarter when Raiders' cornerback Charles Woodson sacked Brady, forcing him to lose the football. The Raiders recovered the ball and all they had to do was run out the clock to advance in the playoffs.

That was until referees overturned the play, saying Brady's arm was moving forward, thus making it an incomplete pass and not a fumble. The refs pointed to the "tuck rule," which was eliminated from the NFL rulebook in 2013.

The rest, as they say, is history. Patriots went on to win the game and eventually their first Super Bowl.

DECEPTION

A week before deflate-gate became a household name, there was some controversy swirling around the Patriots' playoff win over the Baltimore Ravens in a tightly contested 35-31 game. Ravens coach John Harbaugh accused the Pats of a "substitution trick" that was "clearly deception."

The Patriots dug into their bag of tricks on their second drive of the third quarter, lining up just four offensive linemen and declaring a normally eligible receiver as ineligible to keep Baltimore off balance. Ravens players were confused about which Patriots to match up with in coverage.

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Shane Vereen #34 of the New England Patriots and Lardarius Webb #21 of the Baltimore Ravens during the 2015 AFC Divisional Playoffs game, Jan. 10, 2015 in Foxboro, Mass.

Harbaugh said it was a tactic that "nobody has ever seen before."

Brady wanted none of that and fired back after the game.

"Maybe those guys gotta study the rulebook and figure it out. We obviously knew what we were doing and we made some pretty important plays. It was a real good weapon for us," he said.

DEFLATE-GATE

The latest controversy surrounds accusations the team used under-inflated balls in their 45-7 rout of the Indianapolis Colts to earn their sixth trip to the Super Bowl.

According to ESPN, 11 of the 12 balls used by the team were under-inflated by two pounds per square inch. Footballs, which are weighed before the game, must be inflated to no less than 12.5 pounds per square inch.

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Tom Brady during the AFC Championship Game between the New England Patriots and the Indianapolis Colts, Jan. 18, 2015, Foxborough, Mass.

A deflated ball could be easier for the quarterback to grip in bad weather, such as in Sunday's rain at Gillette Stadium in Foxborough, Massachusetts.

The NFL is investigating and Belichick said this earlier this week that his team will cooperate with the NFL's investigation.